Please note that it is possible to have a double tax residence. This is particularly important in the case of natural persons, where individual states may have different internal regulations determining residence. For example, in the United States, a tax resident is considered to be a person who has the so-called “green card”, regardless of whether that person resides and lives in the United States or not. If, in addition, such a person resides in Poland for more than 183 years, they hold a double tax residence, i.e., they would potentially be subject to taxation on all their income both in Poland and in the USA. A similar situation may also occur in the case of companies. Some countries accept the place of effective management (such as Poland) as the criterion of residence, while others may accept the criterion of formal registration (i.e., where the company was registered).

Double residence issues are settled by agreements on the avoidance of double taxation. In the case of natural persons, the criterion which most often prevails is the so-called centre of vital and economic interests, while in the case of companies, the place of actual management.